This invention relates generally to wireless communications systems. More particularly, it relates to system and method for wireless deployment of Bluetooth access points using a distributed antenna architecture.
Bluetooth, a new universal radio interface, has been developed in recent years, enabling electronic devices to communicate via short-range radio connections. The Bluetooth technology not only eliminates the need for wires, cables and connectors between various electronic devices, it also paves the way for new and completely different devices and communications networks.
Bluetooth can also be advantageously utilized as a complement and an extension to wired and wireless communications networks, thereby enabling wireless communications to be virtually ubiquitous. There is therefore a need in the art for a simple, scalable, and economical way of deploying the Bluetooth technology in various wired and wireless communications networks, so as to enhance the capacity and performance of wireless communications.
The aforementioned need in the art is provided by a wireless communications system of the present invention, in which a distributed antenna system (DAS) is used to extend the range of Bluetooth access points (BTAP) and one or more master Bluetooth access point modules are further utilized to create one or more wireless personal area networks (WPANs) in a scalable and versatile manner.
The distributed antenna system in the present invention employs an effective and scalable architecture that links a main unit to multiple remote units by a signal-transfer means (such as optical fibers, coaxial or CAT5 cables), wherein the remote units are in RF-communication with multiple antennae that are spatially distributed (in an indoor or outdoor environment). The main unit is in RF-communication with an integrated module (IM), which in turn interfaces directly (or indirectly) to a local area network (LAN). One or more master Bluetooth access point modules are in RF-communication with the distributed antenna system, in various configurations as exemplified in the following embodiments. Furthermore, each master Bluetooth access point module is in RF-communication with one or more slave Bluetooth devices, thereby effectively creating a wireless personal area network (WPAN).
In this specification and appending claims, a master Bluetooth access point module generally refers to a master Bluetooth access point radio (M-BTAP), a combination of a wireless LAN (WLAN) radio (e.g., IEEE 802.11b, IEEE 802.11a, HiperLAN, or HiperLAN2) and a master Bluetooth access point radio (WLAN/M-BTAP), or a combination of a master Bluetooth access point radio and any RF radio known in the art. (Note that a Bluetooth access point (BTAP) to a LAN is typically provided by a master Bluetooth radio.)
It should be noted that in this specification, an element is said to be placed in the xe2x80x9cback-endxe2x80x9d of the communications system of the present invention, if it is connected between the main unit of the distributed antenna system and the LAN. An element is said to be placed in the xe2x80x9cfront-endxe2x80x9d of the communications system of the present invention, if it is in RF-communication with the antennae of the distributed antenna system.
In a first embodiment of the communications system of the present invention, one or more master Bluetooth access point modules in the form of master Bluetooth access point radios (M-BTAPs) are pooled in the back-end of the system, serving as the Bluetooth access points (BTAP) to the LAN. The M-BTAPs are in RF-communication with the main unit via an integrated module. In this case, each M-BTAP communicates with multiple slave Bluetooth devices located in the front-end of the communications system via the distributed antenna system, thereby effectively creating a wireless personal area network (WPAN) that is supported by all of the remote units. Moreover, multiple overlapping WPANs can be created by implementing multiple M-BTAPs in the back-end of the system, thereby increasing the Bluetooth coverage density. Such a configuration provides a simple and flexible way of accommodating the Bluetooth coverage density to the Bluetooth traffic demand, without altering the distributed antenna infrastructure.
In a second embodiment of the communications system of the present invention, one or more master Bluetooth access point modules in the form of master Bluetooth access point radios (M-BTAPs) are embedded in at least one of the remote units, wherein each M-BTAP further communicates with one or more slave Bluetooth devices and thereby forms a WPAN. (Note that the M-BTAPs can alternatively be extended from the remote unit in a wired star or cascaded configuration.) In this case, a remote unit can host multiple M-BTAPs, thus supporting multiple overlapping WPANS that altogether provide a coverage area of greater density. (In situations where each remote unit covers a designated area, the WPANs supported by different remote units are also substantially non-overlapping.) This configuration allows a variety of WPANs to be created in the front end of the system in a scalable and versatile manner, without altering the network configuration in the back-end.
In a third embodiment of the communications system of the present invention, one or more master Bluetooth access point modules in the form of master Bluetooth access point radios (M-BTAPs) are pooled in the back-end of the system, serving as the Bluetooth access points (BTAPS) to the LAN. The M-BTAPs are in RF-communication with the main unit via an integrated module. The system further comprises one or more slave/master Bluetooth access point modules (S/M-BTAPs) located in the front-end of the system, in RF-communication with the antenna. In this case, each M-BTAP communicates with one or more S/M-BTAPs via the distributed antenna system; and each S/M-BTAP in turn communicates with one or more slave Bluetooth devices and thereby creates a WPAN. (That is, a slave-master Bluetooth access point module is essentially a dual module of two Bluetooth access point radios, configured such that it is a xe2x80x9cslavexe2x80x9d to an M-BTAP located in the back-end and thus serves as an xe2x80x9cextended Bluetooth access pointxe2x80x9d, and a xe2x80x9cmasterxe2x80x9d to the constituent slave Bluetooth devices in its WPAN.) As such, one M-BTAP (in the back-end) can support multiple S/M-BTAPs (in the front-end); and each S/M-BTAP further supports multiple slave Bluetooth devices. This configuration provides a wirelessly deployment of Bluetooth access points, and an efficient and scalable way of forming a variety of WPANs, as desired in practical applications.
In a fourth embodiment of the communications system of the present invention, one or more master Bluetooth access point modules are distributed in the front-end of the system. In this case, each master Bluetooth access point module is in the form of a combination of a WLAN radio (e.g.,IEEE 802.11b, IEEE 802.11a, HiperLAN, or HiperLAN2.) and a master Bluetooth access point radio (WLAN/M-BATP). The master Bluetooth access point radio in each WLAN/M-BTAP communicates with one or more slave Bluetooth devices, thereby forming a WPAN. And the WLAN radio in the same module serves to communicate with WLAN access points (WLAN APs) (which are typically IEEE802.11 radios) tapped to the LAN, thereby providing access to the LAN and its application server. As such, the distributed antenna system effectively extends the WLAN access points from the back-end to the front-end of the system, at which Bluetooth access points are wirelessly deployed and a plurality of WPANS further created.
In the aforementioned embodiments (and many alternative embodiments according to the present invention), the employment of a distributed antenna system provides an effective and scalable way of extending the range of Bluetooth (or WLAN) access points. And the coupling of various types of master Bluetooth access point modules with the distributed antenna system enables Bluetooth (or WLAN) access points to be wirelessly deployed in the front-end of the system, at locations desired in practical applications. And the WPANs thus created (in overlapping and/or non-overlapping forms) greatly enhance the Bluetooth coverage and thereby increase the system performance. As such, the present invention provides a simplified and easily scalable Bluetooth coverage infrastructure, allows pooling the resources of Bluetooth (or WLAN) access points for best performance/cost ratio and capacity management, and simplifies the provisioning in the front-end.
The wireless communications system according to the present invention may further include a controller (e.g., provided by a processor), in communication with the LAN or the main unit of the distributed antenna system, for performing capacity management. Working together with the application server of the LAN, the controller enables dynamic RF routing/filtering to be performed at the main unit, expansion units and/or remote units, such that a particular group of downlink RF signals (e.g., the downlink RF signals transmitted from a specific M-BTAP or WLAN AP, or a selected group of M-BTAPs or WLAN APs, in the back-end) is directed to one or more designated remote units. And the uplink signals from the designated remote units are in turn routed to the specific M-BTAP (or WLAN AP). This allows various resources in the system to be utilized in an optimal manner, thereby enhancing the overall performance of the system.
It should be noted that the distributed antenna system in the present invention may further include one or more expansion units, each serving as an intermediate hub for facilitating the transportation and distribution of RF signals.
The wireless communications system of the present invention can be implemented in both indoor and outdoor environments, including (but not limited to) airports, malls, office buildings, tunnels, hotels, convention centers and sports arenas.
The novel features of this invention, as well as the invention itself, will be best understood from the following drawings and detailed description.